1. Field of the Invention
The present invention relates to a vehicle anti-thief device and more particularly, to an air pressure induction type vehicle anti-thief device.
2. Description of Related Art
In order to prevent stealing of the car by a thief or occurrence of an accident, the owner of the car may install a anti-thief device in the car. When leaving the car, the owner of the car can initiate the anti-thief device, driving different sensors to detect different abnormal conditions.
When an abnormal condition of the car occurred, for example, an intruder intruded the car, the corresponding sensor is induced to trigger the anti-thief device. Conventional anti-thief devices commonly use a siren to give a sharp sound to threaten the intruder. When heard the sharp sound of the siren, the owner of the car can rapidly come to the place of the car to examine what happened.
However, the sharp sound of the siren of a motor vehicle anti-thief device is hearable within a limited distance. The owner of the motor vehicle may not be able to hear the sharp sound of the siren of the motor vehicle during the occurrence of an abnormality of the motor vehicle. In this case, the owner of the motor vehicle cannot take the necessary step in time. Further, when the motor vehicle is being removed by a wrecker, the owner of the motor vehicle cannot know what is happening if he or she does pot hear the sound of the alarm of the anti-thief device of the motor vehicle. In this case, the owner of the motor vehicle knows that the motor vehicle has been taken away only when returns to the parking place. The aforesaid conditions happened just because the motor vehicle anti-thief device is unable to actively inform the owner of the motor vehicle. In general, a conventional motor vehicle anti-thief device cannot well protect the motor vehicle or actively inform the owner of the motor vehicle of the occurrence of an abnormality of the motor vehicle. Further, the sharp sound of the alarm causes a noise problem to the surroundings.
Therefore, it is desirable to provide a vehicle anti-thief device that eliminates the aforesaid drawbacks.